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			<h1>common_schema</h1> <strong>2.2</strong> documentation
			<div class="subtitle">DBA's framework for MySQL</div>
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				<h2><a href="rdebug_get_variable.html">rdebug_get_variable</a></h2>	
<h3>NAME</h3>
rdebug_get_variable(): Get value of local or user defined variable.

<h3>TYPE</h3>
Function

<h3>DESCRIPTION</h3>
<p>
	This function is part of the <a href="rdebug_api.html">rdebug API</a>.
</p>
<p>
	<i>rdebug_get_variable()</i> returns the value of a single parameter or local 
	or user defined variable currently visible by the <i>worker</i>.
</p>

<p>
	Variables which are visible are those presented by
	<a href="rdebug_watch_variables.html">rdebug_watch_variables()</a>. These are
	the local variables in scope at the <i>worker's</i> currently executing routine,
	and the user defined variables used anywhere by that routine. 
</p>
<p>
	Calling <i>rdebug_get_variable()</i> should take place while the <i>worker</i>
	is being suspended on a <a href="rdebug_set_breakpoint.html">breakpoint</a> or
	by a step (<a href="rdebug_step_into.html">into</a>/<a 
		href="rdebug_step_out.html">out</a>/<a 
		href="rdebug_step_over.html">over</a>). 
	During that time it is possible to call this routine multiple times for same
	variables or for different variables.
</p>
<p>
	This function is provided as convenience: it is sometimes desired to call upon a
	function than to invoke a routine and read its result set.
	It works similarly to <a href="rdebug_watch_variables.html">rdebug_watch_variables()</a>.
	However, it does not return any metadata for the variable. 
</p>
<p>
	Execution of this routine only makes sense on an active debugging session, i.e.
	after calling <a href="rdebug_start.html">rdebug_start()</a>.
</p>

<h3>SYNOPSIS</h3>
<p>
<blockquote><pre>rdebug_get_variable(
    rdebug_variable_name varchar(128)
  ) returns blob
  READS SQL DATA</pre></blockquote>
</p>
<p>
  Input: 
  <ul>
    <li><strong>rdebug_variable_name</strong>: name of local variable or user defined variable. 
    	User defined variables are preceded by <strong>"@"</strong>.
	</li>
  </ul>
</p>


<h3>EXAMPLES</h3>
	<p>
		Compare usage of <a href="rdebug_watch_variables.html">rdebug_watch_variables()</a>
		and <i>rdebug_get_variable()</i>:
	<blockquote><pre>mysql&gt; call rdebug_watch_variables();
+----------------+--------------------------+-------------------+---------------+----------------+
| routine_schema | routine_name             | variable_name     | variable_type | variable_value |
+----------------+--------------------------+-------------------+---------------+----------------+
| test           | analyze_continent_cities | @avg_count_cities | user_defined  | 34.627450980   |
| test           | analyze_continent_cities | @count_countries  | user_defined  | 51             |
| test           | analyze_continent_cities | current_continent | param         | Asia           |
+----------------+--------------------------+-------------------+---------------+----------------+

mysql&gt; select rdebug_get_variable('current_continent') as result_cont;
+-------------+
| result_cont |
+-------------+
| Asia        |
+-------------+

mysql&gt; select rdebug_get_variable('@avg_count_cities') as result_avg;
+--------------+
| result_avg   |
+--------------+
| 34.627450980 |
+--------------+
</pre></blockquote>
</p>


<h3>ENVIRONMENT</h3>
MySQL 5.1 or newer

<h3>SEE ALSO</h3>
<a href="rdebug_set_variable.html">rdebug_set_variable()</a>,
<a href="rdebug_watch_variables.html">rdebug_watch_variables()</a>

<h3>AUTHOR</h3>
Shlomi Noach
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					<h3>DATA</h3>
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						<li><a title="tables" href="tables.html">Tables</a></li>
						<li><a title="variables" href="variables.html">Variables</a></li>
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